This invention relates generally to wireless communications devices, and more particularly, to antenna and button structures for wireless communications devices.
As integrated circuit technology advances, it is becoming feasible to construct portable wireless devices with small form factors. Examples of portable wireless devices include mobile telephones, wireless headsets, digital cameras with wireless capabilities, remote controls, wristwatch-type devices, music players with wireless functions, and handheld computers. Devices such as these are often small enough to be held in the hand and may sometimes be referred to as handheld electronic devices. Larger portable wireless devices include laptop computers.
Portable electronic devices sometimes use antennas to transmit and receive radio-frequency signals. For example, wireless Bluetooth headsets have antennas for communicating with cellular telephones.
For proper antenna operation, an antenna resonating element in a portable wireless device is generally placed at a suitable distance from the conductive structures in the device. Sometimes antennas are mounted externally. This type of arrangement is used, for example, in certain cellular telephone whip antenna arrangements. When a more compact arrangement is needed, an antenna resonating element may be mounted on a printed circuit board in a device. However, to ensure satisfactory performance, it is generally necessary to locate the resonating element on a special portion of the circuit board that has been maintained free of electrical components. If sufficient clearance is not provided for the antenna resonating element in this way, the antenna may fail to operate properly.
In some situations, it is not acceptable to use an external antenna design. Constraints such as a desire for compactness, light weight, and good esthetics can make external designs inappropriate. Similarly, antenna arrangements based on circuit boards in which a large clearance is provided between an antenna resonating element and components mounted on the board may be unsatisfactory because too much board real estate is dedicated to providing the clearance.
It would therefore be desirable to be able to provide improved compact antenna configurations for wireless communications devices.